Oct. 23, 1916 Daily Transpiration during Normal Growth Period 
201 
plotting the ratio of the daily transpiration of one crop to that of the 
other. 
If such ratios depart from unity to any great extent, the difference be¬ 
tween the departure of the ratio and that of its reciprocal is so great that 
the graphs resulting from the plotting of such ratios are not readily com- 
/S/4 <40GUSr 
Fig. 17.—Graphs of the daily ratios of the transpiration of the different crops grown in 1914 plotted loga¬ 
rithmically. F signifies flowering; C indicates the cutting of the crop, which was followed by a new 
growth from the established root system; H, heading; and R, ripening. 
parable. By plotting the logarithm of the ratio, however, the same 
departure is obtained for a ratio and its reciprocal. The transpiration 
ratios of a number of different crops grown in 1914 are shown in figure 
17, plotted logarithmically. 
The first graph represents the ratio of the daily transpiration of Gal- 
galos wheat to the*daily transpiration of Kubanka wheat. The early 
